Until the creation of the first CRISPR babies in 2018, there were two main medical methods for selecting the genetic traits of a child. The first was prenatal testing, which involves performing genetic tests on embryos as they are growing in the womb. Nowadays, such tests can detect Down’s syndrome, sex, and dozens of congenital conditions. Parents can decide to abort the embryo if they don’t like the traits. In the U.S., a prenatal diagnosis of Down’s syndrome results in an abortion approximately two-thirds of the time
The way the test works, or was supposed to work, is that a long swab is inserted into the back of a patient’s nasal passage. The lab uses some of the chemical mixtures in the kit to extract any RNA that is in the mucus. The RNA is then “reverse-transcribed” to turn it into DNA. The DNA strands are amplied into millions of copies using a well-known process called a polymerase chain reaction (PCR), which most college biology students learn how to do. The PCR process was invented in 1983 by Kary Mullis, a chemist at a biotech company. Driving in his car one night, Mullis crafted a way to tag a sequence of DNA and use enzymes to duplicate it through repeated cycles of heating and
cooling known as thermocycling. “Beginning with a single molecule of the DNA, the PCR can generate 100 billion similar molecules in an afternoon,” he wrote.2 These days the process is usually done using a machine the size of a microwave that raises and lowers the temperature of the mixture. If the genetic material of the coronavirus is present in the mucus, the PCR process amplies it so that it can be detected.
The invention of easily reprogrammable RNA vaccines was a lightning-fast triumph of human ingenuity, but it was based on decades of curiosity-driven research into one of the most fundamental aspects of life on planet earth: how genes encoded by DNA are transcribed into snippets of RNA that tell cells what proteins to assemble. Likewise, CRISPR gene-editing technology came from understanding the way that bacteria use snippets of RNA to guide enzymes to chop up dangerous viruses. Great inventions come from understanding basic science. Nature is beautiful that way.
Some of the developers of DNA vaccines, including Inovio, tried to facilitate the delivery into human cells through a method called electroporation, which delivers electrical shock pulses to the patient at the site of the injection. That opens pores in the cell membranes and allows the DNA to get in. The electric pulse guns have lots of tiny needles and are unnerving to behold. It’s not hard to see why this technique is unpopular, especially with those on the receiving end.
Harvard’s Systems, Synthetic, and Quantitative Biology Program, which combines biology and computer science.
The most important next steps will be innovations in “microuidics,” which involves channeling tiny amounts of liquid in a device, and then connecting the
information to our cell phones. That will allow us all, in the privacy of our homes, to test our saliva and blood for hundreds of medical indicators, monitor
our health conditions on our phones, and share the data with doctors and researchers.